Yeah, probably not, but I think it's more likely than some folks realize.
He has only played over 10 minutes once in the last month and they are bringing in a really good FR PG. If that player jumps Holloman on the depth chart, there aren't a ton of minutes. All three of their current starters in their backcourt could return next year. Walker might go pro, but he could return. The other two will likely be back.
Essentially, if Walker does not pro, he is fighting with a 5 star PG (24th ranked nationally) for the same role he had this year.
If Walker does go pro, he is fighting that player for the likely starting spot, but I also wouldn't be shocked if MSU looks for the portal if Walker leaves.
They might like Holloman but programs like MSU don't typically put their program in the hands of a player averaging 1 point and 1 assist per game. That isn't me ripping on Holloman, that just doesn't seem like something Izzo would feel comfortable doing.